* {
    box-sizing: border-box;
}

html, body {
    height: 100%;
    margin: 0;
}

body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    background-color: #f4f4f4;
    display: flex;
    flex-direction: column;
}

.container {
    flex: 1;
    display: flex;
    flex-direction: column;
}

header {
    background: #35424a;
    color: #ffffff;
    padding: 20px 0;
    text-align: center;
}

nav ul {
    list-style: none;
    padding: 0;
}

nav ul li {
    display: inline;
    margin: 0 15px;
}

nav ul li a {
    color: #ffffff;
    text-decoration: none;
}

main {
    padding: 20px;
    flex: 1;

}

div {
    background: #ffffff;
    margin: 20px 0;
    padding: 15px;
    border-radius: 5px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

div .img {
    display: block;
    margin: 20px auto;
    max-width: 100%;
    height: auto;
}
section{
    display: flex;
    flex-direction: column;
    align-items: center;
}

footer {
    text-align: center;
    padding: 10px 0;
    background: #35424a;
    color: #ffffff;
}
